Boring head



C. E. DAVIS.

BORING HEAD.

APPLICATION FILED 11111.17,1921.

1,4; EQAQ8, 111611 111111 13, 1922.

CECIL E. DAVIS, OF MONTEZUMA, KANSAS.

resins HEAD.

Application filed January 17, 1921.

To all whom it may concern:

Be it known that T, Cnorr. DAVIS, a citizen oil the United States,residing at lliontezuma, in the county of Gray and State of Kansas, haveinvented certain new and useful Improvements in Boring Heads, of whichthe following is a specification.

This invention relates to boring heads and it comprises a body portionhaving mounted therein radially adjustable cutters, means for expandingsaid cutters outwardly, and means for withdrawing said cutters when saidexpanding means has been withdrawn, said withdrawing means being adaptedalso 5 to coact with said expanding means for looking the cutters in anyselected position within their limits of movement.

An important object of the invention is to provide a boring head whereinthe adjustable cutters may be quickly and easily set and locked withoutthe use of set screws.

Other objects and advantages of the in vention will be apparent duringthe course of the following description.

In the drawings forming a part of this specification and in which likenumerals are employed to designate like parts throughout,

Figure 1 is a side elevation of the tool assembled,

Figure 2 is a central longitudinal sectional view through the device,

Figure 3 is a section taken on line 33 of Figure 2,

Figure a is a similar view taken on line 4; 1 of Figure 2, and,

Figure 5 is a detail perspective of the cutters and the expandingmember.

In the drawings, wherein for the purpose of illustration is shown apreferred embodiment ofthe invention, the numeral 10 designates the bodyportion of the tool as a whole. The body portion 10 includes arelatively large cylindrical portion 11 at one end thereof and arelatively small threaded end 12 adapted for connection with anysuitable source of power. The body portion 10 further includes anintermediate tapered portion 13 connecting the cylindrical portion 11with the threaded end 12. The outer end of the cylindrical portion 12 isprovided with a bore 14:, and the inner end thereof is provided with aninternally threaded bore 15 communicating with the bore 14c. The

inner end of the bore 15 communicates with a radial slot 16., whichextends throughout Specification of Letters Patent.

Patented June 13, 1222.

Serial no. 437,86 l.

the length of the tapered portion 13 and a short distance into thecylindrical portion 11 ot the body portion.

As shown in Figures 2 and i, a plurality of cutters 17 are mounted inthe slot 16. The body portions of the cutters are oblong incross-section and of substantially the same width as the slot 16. Asclearly shown in Figure 2, the inner and outer edges of the bodyportions of each of the cutters are parallel, and inclined with respectto the axis of the body portion. The cutters are provided with the usualcutting edges 18.

A screw-threaded plug 19 is mounted in the threaded bore 15 and providedin its outer end with a slot 20 for the reception of a screw driver orthe like. The inner end of the plug 19 carries a preferably integralshank 21 having a cylindrical head 22 se cured to its end.

The numeral 23 designates an expanding member or wedge which is oblongin crosssection and of substantially the same width asv the slot 16. Thefaces 2 1 of the expanding member are adapted to contact the sides ofthe slot 16 to prevent rotation of the eX- panding member with respectto the body portion.

As shown in Figure 2, the edges of the expanding member are inclined tocorrespond to the inclination of the inner edges of the cutters and areadapted to bear thereagainst to move the cutters outwardly upon movementin one direction of the expanding member. The member 24 is provided inits larger end with a T slot 25 to receive the shank 21 and head 22.

A locking member 26 is provided in the form of a sleeve, to limit theoutward move ment of the cutters to any selected position. One end ofthe sleeve 26 is internally screw-threaded, as at 27, to receive theinner portion of the member 12. The inner end of the sleeve 26 isprovided with a conical opening 28, the sides of which are inclined atan angle corresponding to that of the outer edges of the cutters 17. Theouter end of the sleeve 26 may be formed polygonal in shape as at 29 toreceive a wrench or the like when it is desired to clamp the cutters 17in position.

The operation of the device is as follows:

hen it is desired to set the cutters at an increased diameter, thesleeve 26 is rotated to withdraw it from contact with the outer edges ofthe cutters. The plug 19 is then screwed inwardly by means of a screwdriver or the like, the inner face of the head 22 engaging against theinner face of the slot to move the expanding member 23 inwardly. Tieedges of the expanding member, engaging against the inner edges or thecutters, move the latter outwardly until the desired diameter of thecutting edges has been reached. The sleeve 26 is then rotated to move itinwardly and a vrench applied to the polygonal end 29 thereof to tightenthe surfaces of the conical recess 28 against the outer edges of thecutters. When it is desired to decrease the diameter of the cuttingedges the sleeve 26 turned slightly to loosen its connection with thecutters, whereupon the plug 29 may be withdrawn. The sleeve 26 is thenrotated to move it inwardly and the surface of the conical recess,engaging the outer edges of the cutters, will move the latter toward theaxis of the tool until the desired diameter has been reached whereuponthe plug 19 may be rotated until the expanding member 23 grips againstthe cutters to hold them firmly in the desired position.

it is to be noted that means have been provided for both expanding andcontractthe cutting members and that the cutting members are firmlyengaged on opposite sides to hold them firmly in the desired position.

While the form of my invention herewith shown and described is to betaken as a preferred example or the same, it is to be understood thatvarious changes may be made in the size, shape and arrangement of partswithout departing from the spirit 1,41 seas of the invention or thescope of the subjoined claims.

I claim:

1. A boring head comprising a body portion provided with a threaded boreand a radial slot communicating with said bore, a plurality of cuttersmounted in said slot, an expanding member mounted in said slot betweensaid cutters, said expanding memher being provided in one end with asubstantially i -shaped slot, a threaded plug mounted in the threadedbore of said body portion, said plug being provided with a shank andhead adapted to be received in the slot of said expanding member, andmeans for locking said cutters against outward movement.

2. A boring head comprising a body portion provided with threaded boreand a radial. slot communicating with said bore, a plurality of cuttersmounted in said slot, an expanding member mounted in said slot betweensaid cutters, said expanding member being provided in one end with asubstantially T shaped slot, a threaded plug mounted in the threadedbore of said body portion, said plug being provided with a shank andhead adapted to be received in the slot of said expanding member, and alongitudinally movable sleeve carried by said body portion and adaptedto contact the outer surfaces of said cutters.

lin testimony whereof I aflix my signature in presence of two witnesses.

CECIL E. DAVIS.

i Vitnesses:

ALTON N. DAVIS, A. J. CLARK.

